(1) Field of the Invention
The present invention generally relates to a disk drive and a disk cartridge, and more particular to a disk drive including an erroneous insertion preventing device which prevents erroneous insertion of a disk cartridge, and a disk cartridge for use with the disk drive.
(2) Description of the Related Art
Magnetic disk drives are widely used as storage devices of computers. Some magnetic disk drives are a built-in type, and others are externally installed in the computer. A floppy disk drive is a type of the magnetic disk drive. The floppy disk drive is inexpensive, and a floppy disk for use with the floppy disk drive is small in size and light-weight. For this reason, the floppy disk drive has been frequently used as the storage device of the computer.
FIG. 11 shows an existing disk cartridge 10 which contains a normal-capacity disk. The disk cartridge 10 is, for example, a floppy disk cartridge containing a floppy disk having a storage capacity of 1.44 megabytes.
As shown in FIG. 11, the disk cartridge 10 contains a disk 14 accommodated in a hard case 12. The disk 14 is a recording medium for recording information. The case 12 is made of a resin and molded into a generally rectangular form. The cartridge 10 has a predetermined insertion direction, indicated by the arrow "X1" in FIG. 11, in which the cartridge 10 is inserted into a disk drive (not shown).
The cartridge 10 includes a cut-off portion 38 provided at a given one of corners of the case 12 on its front edge confronting the disk drive when the cartridge 10 is inserted in the insertion direction X1. The cut-off portion 38 includes a slanted surface which extends at an angle with the insertion direction X1. The cartridge 10 includes corners 40a, 40b and 40c of the case 12 other than the cut-off portion 38. Each of the corners 40a through 40c is generally right-angled.
The case 12 includes an opening at a position where the disk 14 contained in the case 12 is overlaid, and a shutter 16 is provided to close the opening in a non-loaded condition in which the cartridge 10 is not inserted into the disk drive.
Further, the cartridge 10 includes, as shown in FIG. 11, a write protection hole 13 and a disk type identification hole 15 which are provided in the case 12 adjacent to the corner 40b and the corner 40c, respectively.
FIG. 13 shows a conventional disk drive which is configured to access the disk of the cartridge shown in FIG. 11.
When the cartridge 10 in the correct position is inserted into a conventional disk drive 20 shown in FIG. 13, the shutter 16 is connected to a latch lever 28 of the conventional disk drive 20 so that the shutter 16 is transversely moved by the latch lever 28 to open the opening of the case 12. A read/write head of the conventional disk drive 20 is brought into contact with the disk 14 through the opening of the case 12, so as to read information from or write information to the disk 14.
However, if the cartridge 10 in a wrong position can be inserted into the conventional disk drive 20, the shutter 16 is not properly connected to the latch lever 28, which does not allow the movement of the shutter 16 to open the opening of the case 12. Further, the read/write head of the conventional disk drive 20 may be hit by the inserted cartridge 10, which will damage the read/write head.
Accordingly, in order to eliminate the above-mentioned problem, the insertion position in which a disk cartridge is inserted into a disk drive are predetermined with respect to the insertion direction of the disk cartridge. With respect to the disk cartridge 10, it is necessary to allow the insertion of the cartridge 10 into the conventional disk drive 20 only when the cartridge 10 in the correct position, as shown in FIG. 11, is placed into the conventional disk drive 20 in the insertion direction X1. To achieve this, the conventional disk drive 20 is provided with an erroneous insertion preventing device 42 which serves to prevent erroneous insertion of a disk cartridge into the conventional disk drive 20.
As shown in FIG. 13, the conventional disk drive 20 includes a frame 22 in which various elements of the conventional disk drive 20 are accommodated. The conventional disk drive 20 is provided with a disk loading device 30. The disk loading device 30 includes a slider 24 movably supported on the frame 22, a holder 26 provided within the slider 24, and a latch lever 28. A head carriage 32 which carries a read/write head in a radial direction of the disk is provided on a top surface of the frame 22, and the head carriage 32 is moved by a stepping motor 33. A turntable 34 on which the disk 14 is mounted and rotated is provided in the frame 22. A disk rotating motor which rotates the turntable 34 is provided on a back surface of the frame 22.
The holder 26 is formed from a sheet metal by press forming. The holder 26 includes an internal space for accommodating the disk cartridge 10 when inserted in the conventional disk drive 20. The holder 26 has side walls on which transversely extending pins 36a, 36b, 36c and 36d are provided. The slider 24 has side walls in which slanted grooves (not shown) are formed. The pins 36a through 36d of the holder 26 are connected to the slanted grooves of the slider 24 to guide and support the movement of the slider 24.
The latch lever 28 is rotatably supported on a shaft 44, and the shaft 44 is embedded on the frame 22. A helical torsion spring 46 is fixed to the shaft 44 and connected to the latch lever 28. The spring 46 exerts an actuating force on the latch lever 28 so as to rotate the lever 28 around the shaft 44 in a direction indicated by the arrow "A" in FIG. 13.
As described above, when the cartridge 10 in the correct position is inserted into the holder 26 of the conventional disk drive 20, the shutter 16 is connected to the latch lever 28 so that the shutter 16 is transversely moved by the latch lever 28 to open the opening of the case 12. Further, when the cartridge 10 is moved to a given disk loading point within the holder 26, the connection of the latch lever 28 and the slider 24 is canceled. A spring (not shown) is connected to the slider 24 and exerts an actuating force on the slider 24 so as to push the slider 24 in an ejection direction indicated by the arrow "X2" in FIG. 13.
The latch lever 28 is provided with an internally formed hook 48, and the hook 48 is connected to the slider 24. When the cartridge 10 is ejected out of the conventional disk drive 20, the hook 48 is connected to the slider 24 so as to restrict the movement of the slider 24.
When the latch lever 28 is rotated by the inserted cartridge 10, the hook 48 is separated from the slider 24 so that the slider 24 is moved in the ejection direction X2 by the actuating force of the spring. The holder 26 in which the cartridge 10 is held is lowered by the movement of the slider 24. This makes the cartridge 10 be mounted on the turntable 34. The read/write head held on the head carriage 32 is brought into contact with the disk 14 through the opening of the case 12.
In the conventional disk drive 20 of FIG. 13, the erroneous insertion preventing device 42 is provided on the holder 26. The erroneous insertion preventing device 42 serves to prevent erroneous insertion of a disk cartridge into the holder 26 of the conventional disk drive 20.
As shown in FIG. 13, the erroneous insertion preventing device 42 includes a helical torsion spring 50 and a groove 52 formed in the holder 26. The spring 50 has a coil portion 50a in the middle of the spring 50, an arm portion 50b at one end, and an extended arm portion 50c at the other end. A rib 54 is integrally formed with the holder 26, and the coil portion 50a is fixed to the rib 54. A rib 56 is integrally formed with the holder 26, and the arm portion 50b is connected to the rib 56. The extended arm portion 50c is passed through the groove 52 and projects toward the internal space of the holder 26.
The helical torsion spring 50 is attached to the holder 26 in the above-described manner. The extended arm portion 50c of the spring 50 is movable within the groove 52 in one of directions indicated by the arrows "B1" and "B2" in FIG. 13. When the cartridge 10 is not inserted into the holder 26, the extended arm portion 50c is actuated in the direction B1due to an actuating force of the spring 50 and pressed against the end of the groove 52. The spring 50 is arranged on the holder 26 such that the leading edge of the extended arm portion 50c confronts the cut-off portion 38 of the cartridge 10 when the cartridge 10 in the correct position is inserted into the holder 26 in the insertion direction X1.
FIG. 14A through FIG. 14C are diagrams for explaining a function of the erroneous insertion preventing device of the conventional disk drive shown in FIG. 13.
As shown in FIG. 14A, when the cartridge 10 in the correct position is inserted into the holder 26, the cut-off portion 38 of the cartridge 10 confronts the leading edge of the extended arm portion 50c. The cut-off portion 38 includes the slanted surface extending at an angle with the insertion direction X1. The extended arm portion 50c is actuated in the direction B2 by the cut-off portion 38 of the inserted cartridge 10.
Hence, as shown in FIG. 14B, the insertion of the cartridge 10 into the holder 26 is allowed when the cartridge 10 in the correct position is inserted.
However, as shown in FIG. 14C, when the cartridge 10 in a wrong position is inserted into the holder 26, the corner (for example, the corner 40a) of the cartridge 10, other than the cut-off portion 38, confronts the leading edge of the extended arm portion 50c. The extended arm portion 50c is not actuated in the direction B2 but pressed against the end of the groove 52 in the direction B1. The insertion of the cartridge 10 in the wrong position is stopped by the extended arm portion 50c. Hence, the insertion of the cartridge 10 in the wrong position into the holder 26 is prevented by the erroneous insertion preventing device 42.
With recent developments of high-speed computers and demands for increases of the amount of data processed by the computers, a disk drive which is configured to access an increased-capacity disk has been proposed. In order to ensure the compatibility of the increased-capacity disk drive with the normal-capacity disk, it is desirable to provide a disk drive which is capable of accessing each of the normal-capacity disk and the increased-capacity disk, as well as a disk cartridge containing the increased-capacity disk for use with the disk drive.
FIG. 12 shows a conceived disk cartridge containing an increased-capacity disk. The disk cartridge shown in FIG. 12 is conceived from the disk cartridge 10 so as to allow for use with a disk drive configured to access an increased-capacity disk.
Hereinafter, a disk cartridge containing an increased-capacity disk will be called the first disk cartridge. A disk drive configured to access the increased-capacity disk will be called the first disk drive. The disk cartridge 10 containing the normal-capacity disk will be called the second disk cartridge. The conventional disk drive 20 configured to access the normal-capacity disk will be called the second disk drive.
As shown in FIG. 12, the disk cartridge 60, which is the first disk cartridge, has a configuration which is essentially the same as that of the disk cartridge 10 which is the second disk cartridge. The cartridge 60 contains an increased-capacity disk 64 accommodated in a hard case 62. The disk 64 is, for example, an increased-capacity disk having a storage capacity of 200 megabytes. The case 62 is made of a resin and molded into a generally rectangular form. The cartridge 60 has a predetermined insertion direction, indicated by the arrow "X1" in FIG. 12, in which the cartridge 60 is inserted into a disk drive (not shown).
The cartridge 60 includes a cut-off portion 68 provided at a given one of corners of the case 62 on its front edge confronting the disk drive when the cartridge 60 is inserted in the insertion direction X1. The cut-off portion 68 includes a slanted surface extending at an angle with the insertion direction X1. The cartridge 60 includes corners 70a, 70b and 70c of the case 62 other than the cut-off portion 68. Each of the corners 70a through 70c is generally right-angled.
The case 62 includes an opening at a position where the disk 64 contained in the case 62 confronts, and a shutter 66 is provided to close the opening in a non-loaded condition in which the cartridge 60 is not inserted into the disk drive.
Further, the cartridge 60 includes, as shown in FIG. 12, a write protection hole 63 and a disk type identification hole 65 which are provided in the case 62 adjacent to the corner 70b and the corner 70b, respectively. The disk type identification hole 65 of the cartridge 60 is larger than the disk type identification hole 15 of the cartridge 10. Only the disk type identification hole 65 is different from the disk type identification hole 15, in order to allow a disk drive to identify the type of the disk cartridge inserted into the disk drive.
As described above, the first disk cartridge and the second disk cartridge are different from each other only in the size of the disk type identification hole. However, the capacity of the disk 64 of the first disk cartridge 60 is much larger than the capacity of the disk 14 of the second disk cartridge 10. Suppose a first disk drive which is configured to access each of the increased-capacity disk and the normal-capacity disk. If the first disk drive is provided with a detecting device which detects the type of the inserted disk cartridge by sensing the size of the disk type identification hole, it is possible for the first disk drive to detect which of the first disk cartridge and the second disk cartridge is inserted into the first disk drive.
Hence, it is conceivable to provide the above-mentioned first disk drive with an erroneous insertion preventing device which is the same as the error insertion preventing device 42 of the second disk drive 20. Similar to the second disk drive 20, the conceived first disk drive prevents the insertion of the first disk cartridge 10 or the second disk cartridge 60 in a wrong position into the holder by means of the erroneous insertion preventing device.
However, if the first disk cartridge 60 shown in FIG. 12 is used with the second disk drive 20 shown in FIG. 13, the extended arm portion 50c of the second disk drive 20 allows the insertion of the first disk cartridge 60 into the holder 26 when the first disk cartridge 60 in the correct position is inserted into the second disk drive 20. The read/write head of the second disk drive 20 uses a configuration and a head-contact pressure which are different from those used by the read/write head of the first disk drive. When the disk 64 of the first disk cartridge 60 is accessed by the second disk drive 20, the recording surface (or a magnetic layer) of the disk 64 may be significantly damaged by the read/write head of the second disk drive 20. The information stored in the disk 64 may be lost or an additional access to the disk 64 may be impossible.